September 2017 PNW Discussion Thread

[Thunder98]

Went down to 36F this morning in Olympia, WA. 

 

http://www.wrh.noaa.gov/mesowest/getobext.php?wfo=sew&sid=KOLM&num=72&raw=0

[TT-SEA]

12Z ECMWF control run shows some warm air during the 11-15 day period to end the month.   This is the 5 day mean... 850mb temps. 

 

[Phil]

God f***** D****T.

It's not a stable pattern like early September, though. Verbatim, the enhanced convection only takes ~ 12 days to cycle through the Pacific, and we're far enough out that this could reverse completely.

 

Just an interesting trend given we're in a state that would statistically favor less Pacific convection going forward, rather than more.

[TT-SEA]

Absolutely gorgeous day.  

[Deweydog]

It will cool down after it warms up after it cools down and rains.

[Geos]

Not sure... it might increase the snowfall for all of King County.

 

On the other hand... without that gap in the Cascades my area would see much less snow and be dependent entirely on elevation.  

 

Yeah it be more like how Portland and Vancouver gets there big snows with the east flow going through the mountain gaps.

[wx_statman]

God f***** D****T.

 

1970. Developing Nina. 

 

37 on 9/14

36 on 9/24

88 on 9/27

90 on 10/2

 

Ridging returned with a vengeance in late Sep, but the winter turned out just fine. 

[TT-SEA]

1970. Developing Nina. 

 

37 on 9/14

36 on 9/24

88 on 9/27

90 on 10/2

 

Ridging returned with a vengeance in late Sep, but the winter turned out just fine. 

 

I don't think he is worried about winter.   He just wants a cold, troughy October.

[wx_statman]

It's not a stable pattern like early September, though. Verbatim, the enhanced convection only takes ~ 12 days to cycle through the Pacific, and we're far enough out that this could reverse completely.

 

Just an interesting trend given we're in a state that would statistically favor less Pacific convection going forward, rather than more.

 

We'll have Typhoon Talim ejecting to the NE of Japan by Tuesday as well. Will be interesting to see what effects that will bring to the wavetrain down the line. 

[Jesse]

1970. Developing Nina.

 

37 on 9/14

36 on 9/24

88 on 9/27

90 on 10/2

 

Ridging returned with a vengeance in late Sep, but the winter turned out just fine.

I'm actually just fine. Kind of giving people what they want.

[Jesse]

It's not a stable pattern like early September, though. Verbatim, the enhanced convection only takes ~ 12 days to cycle through the Pacific, and we're far enough out that this could reverse completely.

 

Just an interesting trend given we're in a state that would statistically favor less Pacific convection going forward, rather than more.

Like I've said. If you are going to bust due to something unexpected coming up, it will always be towards things being ridgier than anticipated for us. Not troughier. Your ridge forecast usually verify and then some, with little to no issues.

[Phil]

Like I've said. If you are going to bust due to something unexpected coming up, it will always be towards things being ridgier than anticipated for us. Not troughier. Your ridge forecast usually verify and then some, with little to no issues.

Haha, well (so far) the trough forecast has verified too. Maybe the pattern will just cycle faster than I was thinking. Wouldn't be the first time that's happened.

[TT-SEA]

Haha, well (so far) the trough forecast has verified too. Maybe the pattern will just cycle faster than I was thinking. Wouldn't be the first time that's happened.

 

If it doesn't cycle faster than you think then that will be the first time that has ever happened.   

[Phil]

If it doesn't cycle faster than you think then that will be the first time that has ever happened.

Could very well be. Long range, I seem to run 5-8 days too slow with pattern progression. It's maddening, tbh.

[Front Ranger]

Went down to 36F this morning in Olympia, WA. 

 

http://www.wrh.noaa.gov/mesowest/getobext.php?wfo=sew&sid=KOLM&num=72&raw=0

 

Would have been record territory a week ago.

[Jesse]

Could very well be. Long range, I seem to run 5-8 days too slow with pattern progression. It's maddening, tbh.

Seems like it would be an easy thing to correct for, but maybe there are nuances I'm not aware of.

 

So if things do get ridgy the last part of September do you seeing it as being short lived overall? I thought for sure ridging would stay off to our northwest for the rest of the month given the progression. Certainly more sunny and even warm days but nothing like the big fat ridge the Euro parks right over us at days 9-10. Seems like a return to the pattern we were seeing before what you were saying was a big shift.

[TT-SEA]

Seems like it would be an easy thing to correct for, but maybe there are nuances I'm not aware of.

 

So if things do get ridgy the last part of September do you seeing it as being short lived overall? I thought for sure ridging would stay off to our northwest for the rest of the month given the progression. Certainly more sunny and even warm days but nothing like the big fat ridge the Euro parks right over us at days 9-10. Seems like a return to the pattern we were seeing before what you were saying was a big shift.

 

 

My guess is the October ridging he sees is actually the late September ridging.   

 

Then there will be a big trough in the first part of October and then there will be a prediction of early November ridging which actually come later in October.  

[epiceast]

The new EPS weeklies do revert to the ridge west/trough east pattern next month. Looks like some Pacific convection, though it appears to be transitory in nature.

 

Will be interesting to see how it unfolds. Looks like a difficult pattern to forecast either way with tropical cyclones everywhere.

Would be nice to get some backpacking weather in October after Snowy the bear put out all the fires.

[Phil]

Seems like it would be an easy thing to correct for, but maybe there are nuances I'm not aware of.

It's more complicated because it's not just timing waves but gauging the synchronization of waves of different phase periods/frequencies. It's interesting, as I'm not the only young forecaster who struggles with a slow bias. I don't know anyone with a fast bias, though.

 

So if things do get ridgy the last part of September do you seeing it as being short lived overall? I thought for sure ridging would stay off to our northwest for the rest of the month given the progression. Certainly more sunny and even warm days but nothing like the big fat ridge the Euro parks right over us at days 9-10. Seems like a return to the pattern we were seeing before what you were saying was a big shift.

The shift is absolutely real, but it's also lower frequency so there will be bumps and blips in the trend towards -PNA/-NAO. Look at the high latitudes right now..for the first time in what seems like forever, that Black Hole over the Hudson Bay/Greenland has been replaced with a big anticyclone. The subtropical NPAC is also developing the -PNA loading pattern. The transition is a complicated process though..it will take more than a few weeks to complete.

[Deweydog]

I'm actually just fine. Kind of giving people what they want.

[Phil]

My guess is the October ridging he sees is actually the late September ridging.

 

Then there will be a big trough in the first part of October and then there will be a prediction of early November ridging which actually come later in October.

That wasn't a prediction, I was just reporting what the weeklies are showing. I don't know whether they're correct or not, yet.

 

I've been forecasting a jet extension/Aleutian cyclone and intermountain west ridging starting during the second week of October. Maybe it'll happen during the first week of October, or maybe something else will happen.

[Deweydog]

Looks like PDX will be starting another streak today!

[TT-SEA]

It's more complicated because it's not just timing waves but gauging the synchronization of waves of different phase periods/frequencies. It's interesting, as I'm not the only young forecaster who struggles with a slow bias. I don't know anyone with a fast bias, though.

 

 

The shift is absolutely real, but it's also lower frequency so there will be bumps and blips in the trend towards -PNA/-NAO. Look at the high latitudes right now..for the first time in what seems like forever, that Black Hole over the Hudson Bay/Greenland has been replaced with a big anticyclone. The subtropical NPAC is also developing the -PNA loading pattern. The transition is a complicated process though..it will take more than a few weeks to complete.

 

 

Your slow bias is very consistent... regardless of the reason.   Just manually adjust for it every time and you will be much closer to reality.   I now manually adjust for you.  

[Deweydog]

Your slow bias is very consistent... regardless of the reason. Just manually adjust for it every time and you will be much closer to reality. I now manually adjust for you.

Manually adjust too much and you'll go blind.

 

#godandyourdeadgrandmotherarewatching

[wx_statman]

Looks like PDX will be starting another streak today!

 

Coulda still been THE streak...

[Phil]

Similar to the Euro seasonal, the JMA seasonal also has an insanely strong NPAC jet during November.

 

Check out these zonal wind anomalies.

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/F73AC033-E6A7-4D83-96F2-C55B0F368136_zpsj8h6in5e.jpg

[TT-SEA]

Similar to the Euro seasonal, the JMA seasonal also has an insanely strong NPAC jet during November.

 

Check out these zonal wind anomalies.

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/F73AC033-E6A7-4D83-96F2-C55B0F368136_zpsj8h6in5e.jpg

 

 

I like a strong jet in November.   Right when it should happen and then usually turns cold and snowy for December and January here.  

[Jesse]

Coulda still been THE streak...

 

I've been sitting in the field by the airport the last four hours. Where are you?

[TT-SEA]

I've been sitting in the field by the airport the last four hours. Where are you?

 

Wearing all black?  

[Phil]

[wx_statman]

I've been sitting in the field by the airport the last four hours. Where are you?

 

It was at 10. You were late so we wrapped things up without you. 

[TT-SEA]

Kinda OT, but it's crazy to imagine what the climate would have been been like during the last ice age. Sea ice pushing all the way down to Baja California is pretty hard to visualize.

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/1939CD82-F9FD-472F-85B7-67337D49BA53_zpsmqiog4c3.jpg

 

That map is messed up.    I doubt the Rocky Mountains were that far west during the last ice age just 15,000 years ago.  

[Front Ranger]

Manually adjust too much and you'll go blind.

 

#godandyourdeadgrandmotherarewatching

 

Tim manually adjusts for Phil, all the time...

[Phil]

That map is messed up. I doubt the Rocky Mountains were that far west during the last ice age just 15,000 years ago.

I can't tell if you're trying to be funny, or if the location of that label is actually bothering you.

[TT-SEA]

I can't tell if you're trying to be funny, or if the location of that label is actually bothering you.

 

Its a rudimentary map... its makes it hard to take the information presented seriously.   Its like a 3rd-grader drew it.  

[Deweydog]

Its a rudimentary map... its makes it hard to take the information presented seriously. Its like a 3rd-grader drew it.

I actually thought the same thing at first glance. Very randomly labeled. Weird.

[Front Ranger]

Its a rudimentary map... its makes it hard to take the information presented seriously.   Its like a 3rd-grader drew it.  

 

It looks like it's labeled from a viewpoint in the middle of the Pacific.

[Geos]

I like a strong jet in November.   Right when it should happen and then usually turns cold and snowy for December and January here.  

 

And it looks like the core of the jet stream will be focused a little south of here, putting us on the north side of storms.

[Geos]

Its a rudimentary map... its makes it hard to take the information presented seriously.   Its like a 3rd-grader drew it.  

 

Yeah it is over simplified. Your missing the Vashon Lobe/glacier that pushed all the way to Olympia!

[Phil]

It looks like it's labeled from a viewpoint in the middle of the Pacific.

Yeah, I flipped it around. The original view was from the Pacific.